Two stage rotary mill



June'5, 1945A-4 R. c. HOPKINS 2,377,495

TWO STAGE ROTARY MILL Filed Nov. 5, 1942 3 Sheets-Sheet l June 5, 1945. R, c. HOPKINS TWO STAGE ROTARY MILL Y 3 Sheets-Sheet 2 Filed Nov. 5, 1942 Jullie 5, 1945- RQ c. HOPKINS TWO STAGE ROTARY MILL Filed Nov. 5, 1942 3 Sheecs-Sheerl 3 Patented June 5, 1945 NUmfrsp Nsrii'rl1:3;5 PATE-NTV OFFICE# Y fjfamilies-` w f Two STAGEROTARY MI`LL` Roberto. Hopkins, Alliance, ohioA i ApplicationNovember 5, 1942,`SerialxNo.464,563

cclaims. ici. 2411-583) The invention relatesto rotary mills for cutting, mixing and attrition of the heavyparticles of oils,` synthetic rubber constituents,paints,` pigments and other mineral, vegetable and animal matter in fluid state, or: capable. of flowing and v being ground and mixed `with other liquid or plastic substances, and more particularly to a two stage millofthis character. i x i An objcctofrthe invention is the provision of a two stage rotary mill having a primary milling chamber in which the` rst stage of` reductiony is accomplishedsomewhat onfthe` principleof a hammer mill, in which the larger particles are milled down to a` nner grain or particle size and blended, and a secondary' milling `clriarnber in which the rst reduction oriirst` pass material is subjected to further cutting, i grinding, attrition and mixing to suchan extent that itis completely pulverizedand reduced to auuniform4 consistency A and lthoroughly mixed. i

i `A further object of the inventionv is to provide a mill of this character having a primary chamherrin which islocated arotary gang of disks having spaced notches intheir peripheral 'portions, forming Wide, heavy teethA for breaking up the largersize particles to aflner grain sizel -A still further object is the provision of a rotary null in which a perforate, cylindrical screen surrounds the rotary gang of disks, `the peripheral toothedporticns of the` disks. beingii'ocatedfin close proximityto the screen. i i i `Another objectief the invention is to provide a rotary mill of this character in which the perforations of the screen are triangular, or Wshape, with their apices disposed in the direction lof rotation of the rotarygang of disks.

Still another Objectis` the provision of a rotary l mill `ofthe character referred toI in whichthe primaryfchambcr is divided into two compart` ments, the inlet tothe chamber communicating with yone compartment and the outlet communicating with the other compartment, the `cylindric screen having an inlet openingwithin the inlet compartment,A whereby all ofthematerial entering the` primary chamber must pass through the cylindric screen and be.` milled by the rotary disks before it` passes to the outlet compartment and is discharged from the chamber. A further object is vthe provision in such a` mill of a secondary chamberdivided into a plurality of attrition chambers `by means of radial partition walls having cutting edges in close proximity to the peripheral portionsof the gang'of rotary blades in the the secondary chamber.

A still further object of the invention is: to provide arotary twohstage mill of `this character in which the primary chamber .isprovided With a rotary' gang of disks having wide, heavy teeth around their peripheral portions, and the secondary chamber is provided with a rotary gang of disks having smaller, saw teeth around their peripheral portions.

"Another object isto*pr'ovide such'a two stage mill in which the primaryandsecondary chambers .arelocated in axial alignment and a single drive shaft is journalled longitudinally through bothchambers and hasthe rotary gangs'oi disks mounted thereon,` `the `out1et` of the,` primary chamber communicatingY with the inlet ofthe secondary chamber. A iurtheriobject of the invention is to provide a rotary mill of this character in `which the toothed disks in the primary chamber are spaced` apart a distance considerablygreater than the thickness'iof the disks; 1 The above objects togetherwith others which will be apparent from the accompanying drawings and the `following description, for whichmay be later referred to., may beattained by constructing thejimproved rotary two stage mill in .the manner illustrated. in the drawings, in whiehfq y .t t t Figure ,l is a side elevation' of the two stage mill to Vwhich fthe invention pertains, showing the same mounted with a motor as a completeunit; Fig.` 2, an enlarged, longitudinal sectional view throughthe primary andsecondary chambers;

` Fig3 a transverse sectional view through the primarychamber, taken as on the lined-3, i

Fig. 2; i

dric screenyvhich surrounds the disks in the primary chamber; 1 i Y, i f

glig,` 5, a detached elevation of one of the disks `from the primary chamber; and i from the secondary chamber.

Similar numerals n refer tosimilar `parts throughout thedrawings.` i t The mill and its driving means may be mounted as a unitupon a base l0,`an electric motor Il being preferably provided for `driving the mill and being mounted upon one end portionof the base as shown in Figure 1.

y The shaft I2 of the motor may be axially connected, by a coupling or clutch located within theV guard t3, to the drive shaft |14 of the mill.

This coupling guard may besupported upon the base: l0 as `by the `upright tito which the guard base I9 and connected thereto as by the bolts 22A located through flanges 23 upon the housing, and the primary housing 24 which is mountedupon portion of the cylinder 49 to admit oil or other material to be milled to pass from the inlet compartment I to the interior of the cylinder, and the remainder of the cylinder is provided with a multiplicity of smaller outlet orifices 54 of such size as is required in the first reduction of semisolid material or heavy particles of sludge or the like.

Although these outlet orices may be of circular or other shape they are preferably triangular or V-shape as shown in Fig. 4 and are so positioned that their apices are disposed in the ,v

direction of rotation of the `cutting disks 42,

one side of the secondary housing and secured e.

thereto as by bolts 25. l

A bearing bracket 26 may be attached to the opposite side of the secondary stage housing as by bolts 25 and to the bearing bracket I'I as by bolts 28 for supporting a bearing 29 through which the intermediate portion of the drive shaft I4 may be journalledand` a bearing portion 3U may be formed upon the outer side of the primary housing 24 for housing a bearing 3| in which the reduced outer end portion r32 vof the drive shaft I4 may be journalled.

A cylindric chamber33 is formed within the primary housing 24 and provided at its top with an inlet opening 34 having a flanged coupling 35 attached thereto as bythe screws 36 for connecting a feed pipe 31 which may lead fromfany suitable source of supply -of the oil or other substance to be milled.

The drive shaft I4 extends axially through the cylindric primary Chamber 33 and the hub 38 may be fixed upon the shaft by any usual and well known means such as the key 39. This hub may extend entirely through the secondary chamber 40, within the secondary housing 2l, and is provided with the' annular shoulder 4I intermediate the two chambers.

A plurality of cutting disks 42 is mounted upon the hub 38 within the primary chamber 33 and extends from the shoulder 4I to a point near the endof the hub, at which point a ring flange 43 may be located around the hub and clamped against the adjacent end of the gang of the cutting disks as by a nut 44 threaded upon the adjacent screw threaded yenel portion 45 of 'the hub, thus clamping the gang of disks tightlybetween the shoulder 4I and the ring ange 43.

Each of the disks 42 is provided around'its periphery with spaced V-shape notches 46 forming the wide, slightly tapered teeth 4l periphery of each disk.

As shown in Fig. 2 a plurality of spacers 48 may be placed between each adjacent pair of cutting disks 42 so as to space the disks widely'apart, or

vif desired the spacers may be eliminated and the around the cutting disks may be placed side by side upon the hub throughout the entire length of the primary chamber.

A hollow cylinder 49 surrounds the cutting disks 42 in the primary chamber and is located in close proximity to the peripheries of these cutting disks so that the disks have substantially a running lit within the hollow cylinder.

Radial partition walls 50, upon the interior of the primary housing, extend inwardly toward each other and contact the vouter surface of the cylinder 49 dividing the primary chamber 33 into an upper or inlet compartment 5I and a lower or discharge compartment 52.

An enlarged opening 53 is provided in the upper whereby the large particles or semi-,solids may be reduced in size as they are wedged into these reduced angular portions of these outlet orifices as they are discharged therethrough by the rotation of the cutting disks.

It will be seen that all of the material entering the primary chamber through the inlet 34 must pass from the inlet compartment 5I `into the cylindrie screen 49 where it is acted uponby 'the rotary cutting disks and the heavy particles thereof 4are broken up, blended and screened and discharged through `the outlet 'orifices 54 oi the screen into the outlet compartment from which` the material is discharged through the discharge outlet 55 and passes through the pipe 5B into the bottom of the secondary chamber 49`located within the secondary housing 2|. f

The drive shaft I4 extends axially through this chamber also and is` surrounded throughout the length of the secondary chamber with the hub 45.

Cutting disks 58 arelocated upon the hub eX- tending from the shoulder 4I to a point near the screw threaded end 59 of the hub, at which point aring ange 60 may be located around the 'hub and clamped against the adjacent end of the gang Iof cutting disks as by a nut 5I, threaded upon the end portion 59 ofthe hub, thus tightly clamping the gang of disks between the shoulder -4I and the ring ange 6I.

If desired, rings 62 and 63 may be mounted upon the shaft and clamped into engagement with the nuts44 and 6I respectively, as by the large nuts V64 and 65 mounted upon 1the screwthreaded portions 66 and vIlrespectively of the shaft I4, thus tending to lock the nuts 44 and BI inadjusted position.V

`'Ihe disks 58 may be of lighter gauge than the disks 42 in the primary chamber `and are preferably provided around their peripheral portions with relatively small V-shape teeth 69, so that these disks are in the nature of circularsaw blades. j 'I'he secondary chamber 40 is preferably divided into a plurality of attrition compartments by means of the radial partition walls 69 havingthe cutting edges 'I0 located substantially in peripheral engagement with the disks 58.

The first reducti-on or first pass material is admitted from the primary chamber to the lower front compartment indicated at 'II of the secondary chamber, and after passing through the several compartments of the secondary chamber is discharged from the lower rear compartment of the secondary "chamber throughthe discharge outlet 12.

For the purpose of regulating 4the temperature and pressure of the material being milled a pipe 13`may communicate with the upper portion of the secondary chamber for connectionV of a thermometer 14 and pressure gauge I5, this pipe com# municating with the secondary chamber through theport'l.- r'

l and thenV passes through the opening 53` to the interior ofthe cylindric screenwhere it is en-` aged by the rapidly rotating `cutting disks 42 which` rotate in a clockwise direction iasvieived inFig. 3,1;h`e large teeth uponthesedisks cooper# ating with the inner surface of thek cylinder I8 tofcut `and break upf the semi-solidsand `large particles or sludge, discharging the milled material through tneoutiet princes s4, the direction of rotationA of "the diskstendingto force the material through the jtapered" ends of the outlet orices so thattheaction is to blend as well as to mill down to a iiner grain or particle size.

As the material is discharged through the outlet orifices of the screen 49 into the lower or discharge compartment 52 it passes out of `the prithe secondary chamber and passes progressively through the several attrition compartments it is given a violent agitation within each compartment by means of the rotating cutting disks, the material being thoroughly reduced, mixed and blended as it passes from each compartment to the next until it is iinely discharged through the outlet pipe 12.

I claim: i

l. A rotary mill including a primary chambe and a secondary chamber, means forming a cornmunication between the chambers, an inlet to the `primary chamber, an outlet from the secondary chamber, a plurality of closely spaced, revolving, cutting discs throughout the entire length of the'primary chamber, said discs having spaced,

radial inwardly tapered, V-shape notches 'entirely around their peripheries forming wide, substantially flat peripheral edged teeth therebe tween, the hat peripheral edges of the teeth being considerably wider than the intervening notches and a plurality of closely spaced revolving cutting discs throughout the entire length of the secondary chamber-having relatively smaller V-shape teeth entirely around their peripheries,

` said discs entirely filling said chambers between the inlet and outlet so that all material passing through the chambers will contact the discs.

2. A rotary mill including a primary chamber and a secondary chamber, means forming a communication between the chambers, an inlet to the primary chamber, an outlet from the secondary chamber, aplurality of closely spaced, revolving, cutting discs throughout the entire length of the primary chamber, said discs having spaced, radial, inwardly tapered V-shape notches entirely around their peripheries forming wide, substantially nat, peripheral edged teeth therebetween, the flat peripheral edges of the teeth being considerably wider, than the intervening notches, a hollow cylinder surrounding the cutting discs throughout their entire length and in and outlet soI that all materialvpassing` through the chambers will contactthe'discs.I vif i 3, A rotary milllincluding a primary"`chambe and a secondary chamber, meansforming acom-` munication between the chambers, anr inlet to the primary chamber, an outlet from the'secondary chamber, a plurality of closely spaced, revolving, cutting discs" throughout the entire length or the primary chamber, 'said discs having spaced, radial, inwardly tapered V-shape 'notches Fen- Vtirely around their peripheries forming wide,lsub

stantially at peripheral edgedvteeththerebe# tween, a hollow cylinder surrounding the cutting discs throughout their entire 4lengthv and inl :close proximity to the peripheral flat portions'ofv the teeth, said cylinder having throughout its entire area a multiplicity of closely spaced, relatively small, triangular outlet orifices therein, the apices of the triangular orices being forward relative to the triangle bases with respect to the direction of rotation of the cutting discs', and a plurality of closely spaced, revolving, cutting discs throughout the entire length of the secondary chamber having relatively smaller peripheral teeth entirely around their peripheries, said discs entirely filling said chambers between the inlet and outlet so that all material passing through the chambers will contact the discs.

4. A- rotary mill including a chamber, a plurality of revolving cutting discs mounted within and extending throughout the entire length of the chamber and provided entirely around their to the direction of rotation of the cutting discs,`

an inlet to thecharnber and an outlet from the chamber, said discs entirely blocking the passage between the inlet and outlet so that all material passing through the chambers will contact the discs. i

5. A rotary mill including a chamber, a plurality of closely spaced, revolving, cutting discs mounted within and extending throughout the entire length of the chamber, a multiplicity of wide, outwardly tapered,substantially ilat peripheral edged teeth entirely around the peripheral portion of the discs, a hollow cylinder surrounding the discs throughout their entire lengthl and in close proximity to the peripheral portions thereof, partition walls extending 'from the inner walls of the chamber to the hollow cylinder and close proximity tothe peripheral portions theredividing the chamber into an inlet compartment and a discharge compartment, an inlet in the top of the cylinder communicating with 'the inlet compartment, a multiplicity` of closely spaced, relatively small, triangular outlet orices in the cylinder, throughout the entire area of the cutting discs and communicating with the discharge compartment, the apices of the triangular orifices being forward relative to the triangle bases with respect to the direction of rotation of the cutting discs, means for admitting material to the inlet compartment and means for discharging material from the discharge compartment, said discs entirely blocking the passage between the inlet and outlet so that all material passing through the chambers will contact the discs.

6. A rotary mill including a cylindric chamber.

a kshaft ,concentrically journalled through the chamber, means for rotating the shaft, av multiplicity of revolving cutting discs fixed upon the shaft, means spacing the discs apart a slightly greater distance than the thickness of a disc, there being spaced, radial inwardly tapered, v shaped notches entirely around the peripheral portions ofthe discs forming relatively wide, outwardly tapered, substantially flat peripheral edged teeth upon the peripheral 'portions of the discs between said notches,f'a hollow cylinder surrounding the discs throughoutthe entire length of'the chamber and in close vproximity tothe peripheral portions of thediscs, horizontal partition Walls extending from the inner walls of the chamber to the hollow cylinder and dividing the chamber into an upper` inlet-,compartment and a lower discharge compartment, an inlet in the inlet compartment, there being anl inlet opening in the top of the cylinderx communicating with the inlet compartment, amultiplicity of closely spaced, relatively small,V triangular orifices throughout the entire area 0f thecylinder. communicating with the discharge compartment, the apices of the triangularoriflces being forward relative to the ,triangle bases with respect tothe direction of rotation of the cutting discsrland an outlet in the discharge compartment, said discs entirely blocking the passage between 4theinlet and outlet so that all material passing through the chambers will contact the discs. V

. ROBERT C. HOPKINS. ,I 

